1. Field of the Invention
The present invention relates to a method for reducing a data repository. In particular the inventive method is applicable to reduce an input/output (I/O) definition file.
2. Description of the Related Art
A data repository contains a plurality of records. The data repository is typically organized as a set of directories, which contain one or several records. The directories may be ordered in a hierarchical way, e.g. as a tree structure, where one directory is a subdirectory of the other directory. Alternatively, the directories may be ordered by references between records of one directory to records of another directory.
Modern computer systems are capable of supporting several thousand I/O units, e.g. channels, control units or devices. The task of configuring such a computer system becomes more and more difficult. In particular, the size of the resulting configuration definition file, which is required to define the accessible I/O devices, increases. With more device definitions, the number of the devices within an I/O definition file (IODF) is increasing rapidly.
The I/O definition file is an example of the above data repository. The device definition may correspond with a set of different record types. The I/O definition file may include a set of directories, which contain the records.
To overcome the problem of the large number of I/O units and the resulting size of the corresponding I/O definition file according to a conventional method, the size of I/O definition file space has been extended. But a large I/O definition file requires more virtual storage and an increased processing time, resulting in lower performance.
According to another conventional method, other data structures have been switched. But such data structures are incompatible to the existing access method.